Power transmission

ABSTRACT

A ROTARY FLUID PRESSURE ENERGY TRANSLATING DEVICE HAVING VANE CAM TRACK WITHIN WHICH IS ROTATABLY MOUNTED A ROTOR CARRYING RADIALLY SLIDING VANES TO FORM FLUID INLET AND FLUID OUTLET ZONES LOCATED BETWEEN THE PERIPHERY OF THE ROTOR AND VANE TRACK, AND A SEALING ELEMENT DISPOSED WITHIN THE PERIPHERY OF SAID ROTOR BETWEEN EACH VANE FOR CREATING A SEAL DURING THE TRANSITION OF THE VANES BETWEEN THE FLUID INLET AND FLUID OUTLET ZONES.

March 2,- 1971 I M| 3,567,350

POWER TRANSMISSION Filed Jan. 15, 1969 I 2 Sheets-Sheet 1 INVENTOR. ALB/N .1. NIEMIEC ATTORNEYS March '2, 1971 A, J. NlEMlEC 3,567,350

POWER TRANSMISSION 2 Sheets-Sheet 2 Filed Jan. 15, 1969 FIG. 5

FIG. 2

FIG. 5

FIG.6

, INVENTOR. ALB/N J. N/EM/EC F'IG. 4

ATTORNEYS United States Patent 3,567,350 POWER TRANSMISSION Albin J. Niemiec, Warren, Mich, assignor to Sperry Rand Corporation, Troy, Mich. Filed .Ian. 15, 1969, Ser. No. 791,362 Int. Cl. F01c 19/02 US. Cl. 418112 23 Claims ABSTRACT OF THE DISCLOSURE A rotary fluid pressure energy translating device having a vane cam track within which is rotatably mounted a rotor carrying radially sliding vanes to form fluid inlet and fluid outlet zones located between the periphery of the rotor and vane track; and a sealing element disposed within the periphery of said rotor between each vane for creating a seal during the transition of the vanes between the fluid inlet and fluid outlet zones.

BACKGROUND OF THE INVENTION This invention relates to power transmissions, and is applicable to those of the type comprising two or more fluid pressure energy translating devices, one of which may function as a pump and the other as a fluid motor. More particularly, this invention relates to an improvement in sliding vane type pumps and motors such as the type illustrated in the Letters Patent to D. B. Gardiner, No. 2,967,488.

Units of this type generally comprise a stator including a vane cam track within which is rotatably mounted a rotor, carrying radially sliding vanes to form fluid inlet and fluid outlet working zones located between the periphery of the rotor and the vane track, either of which may be a low or a high pressure working zone dependent upon the pump or motor function of the device. In such devices, the vanes as followers are adapted to follow the cam track and provide proper sealing between the inlet and outlet porting correlated with the fluid inlet and fluid outlet zones. During operation of such a device, the vanes are urged outwardly and into engagement with the track by centrifugal force and also by providing a controlled pressure unbalanced condition between the outer track engaging surface and an inner surface of the vane. It would be desirable to provide such a unit having a re duced number of vanes.

In the current state of the art, the minimum number of vanes required for use in such pumps and motors is dictated by the necessity of maintaining a proper seal between the various fluid zones. Thus, to reduce the number of vanes required in such units would necessarily result in an arcuate increase in the transition zone between the inlet and outlet zones to maintain the required sealing feature. Inasmuch as the remaining portion of the track must provide the arcuate location for the inlet and outlet zones, the same must be reduced in size to accommodate a corresponding increase in the transition zones.

It would thus be desirable to provide such a unit in which the number of vane elements are reduced but without a corresponding reduction in the arcuate size of the inlet' and fluid outlet zones.

SUMMARY OF THE INVENTION This invention comprises a rotary fluid energy translating device of the sliding vane type with a rotor having radial slots with a plurality of vanes slidably mounted therein, in which the vanes extend outwardly into engagement with a cam track forming fluid inlet and fluid outlet zones, and a plurality of sealing elements disposed between each of said vanes between the periphery of the rotor and 3,567,350 Patented Mar. 2, 1971 the cam track during the transition of said vanes from one fluid zone to another.

It is therefore an object of this invention to provide an improved, low cost, eflicient and long wearing fluid pressure energy translating device.

More specifically, it is an object of this invention to provide a fluid pressure energy translating device of the sliding vane type in which a reduced number of vanes is utilized.

It is still another object of the invention to provide such a device in which the rotor element thereof will be capable of withstanding higher pressures and work loads.

It is a further object of this invention to provide such a device having all the advantages previously recited without increasing the overall dimensions of the devices currently in production.

Further objects and advantages of the resent invention will become apparent from the following description, reference being made to the accompanying drawings wherein a preferred form of the present invention is clearly shown.

In the drawings:

FIG. 1 is a longitudinal sectional view of a device embodying the present invention and taken on line 11 of FIG. 2.

FIG. 2 is a sectional view taken on line 22 of FIG. 1.

FIG. 3 is an enlarged partial sectional View of the sealing element illustrated in FIG. 2.

FIG. 4 is a sectional view of another embodiment taken along line 44 of FIG. 1.

FIG. 5 is an enlarged partial sectional view of the seal ing element illustrated in FIG. 4.

FIG. 6 is an enlarged partial sectional view of another embodiment of the sealing element illustrated in FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the several figures, and especially FIG. 1, there is shown a presently preferred, but merely illustrative embodiment of the inventive principles: a fluid pressure energy translating device 10 of the sliding vane type. The housing 11 of pump 10 comprises a vane cam track section 12 sandwiched between the body member 14 and an end cover 16, all of which are secured to each other by means of bolts 18 extending through cover 16 and the cam section 12 into threaded holes in body 14. The body section 14 is provided with an inlet supply connection port 20 having an inlet passage 22 leading therefrom which has branches 24 and '26, respectively terminating in a pair of fluid port openings 28 and 30. An outlet connection port 32 is provided in the end cover 16 which is directly connected to a pressure delivery chamber 34 formed in an enlarged bore 36 within the end cover 16 where a pressure plate 38 is floatably mounted. The pressure plate 38 is urged rightwardly by outlet pressure in the chamber 34 so that the outer portion of the plain side surface thereof and indicated by the numeral 40 is maintained in engagement against an opposing mating surface of the cam ring 12 and the remainder of said surface 40 is maintained in a fluid sealing relationship with the immediately adjoining surface of a rotor 41 and a plurality of vanes 42 carried thereby within the cam section 12. The vanes 42 are slidably mounted in slots formed within rotor 41. Spring 43 initially biases the pressure plate 38 toward the rotor until suflicient pressure builds up within the chamber 34.

The rotor 41 is rotatably mounted within cam section 12 on a splined end 44 of a drive shaft 46 which, in turn, is rotatably mounted within the bearings 48 and 50 located within the body section 14. Shaft 46 is provided with a seal 52 to prevent leakage passing the same during operation, while ring seals 53 and 54 are provided to prevent leakage at the juncture of the can: ring section 12 with the body 14 and the end cover 16.

The inner surface of the cam ring 12 forms a cam track substantially elliptical in shape and is indicated by the numeral 60 against which the outer tips 64 of vanes 42 are adapted to be maintained on contact. The cam track contour and the outer periphery of the rotor define two opposed working chambers indicated by the numerals 68 and 70 which, for the purposes of convenience, may be divided into fluid inlet Zones or fluid delivery zones. The fluid inlet zones are those portions of the working chambers 68 and 70 registering with the opposed fluid inlet openings 28 and 30 in the body member 14. The fluid delivery zones are those portions of the working chambers 68 and 70 registering respectively with opposed arcuate fluid delivery ports 72 and 74 in the pressure plate 33 which are connected to the pressure chamber 34 by means of duplicate passages 75 leading therefrom, one of which is shown in FIG. 1.

The vane track 69 includes an inlet zone ramp extending from A to B, a transition zone, or a true arc portion, extending from B to C, a delivery zone ramp extending from C to D, and another transition zone or true are portion extending from D to E. The track is symmetrical about both major and minor axes; thus, each of the ramp and true are portions from A to E are duplicated in the lower portion of the track. As the ends of the vanes traverse the inlet ramp, the vanes move radially outward with respect to the rotor, and while the vanes traverse the delivery ramp, the vanes move radially inward. In the transition zone or true are portion, the vanes partake of no radial movement; however, the transition zone portion may optionally have a slight rise or incline as is desired.

Thus, as the rotor turns through a complete cycle, the inter-vane spaces will undergo alternate phases of expansion and contraction. The term inter-vane space as used herein refers to that volume bounded by any adjacent pair of vanes, the outer periphery of the otor between said vanes, and the cam track section associated therewith.

The radial vane slots 45 in the rotor are formed by the parallel walls which guide the vanes as they move radially inward and outward and are enlarged to form with the inner ends of the vanes, small enclosed undervane pressure chambers 76 which are supplied with high pressure in a manner to be described hereinafter. Spacing between each pair of vanes is adapted to span the distance between each pair of ports in a manner to provide proper sealing between the inlet and outlet porting connected to the working chambers of the device.

Pressure from the outlet side of the device is continuously transmitted to the undervane chambers by means of an annularly shaped recess 78 formed on the pressure plate 38 adjacent the undervane pressure chambers. For the purpose of balance, a second annular recess 79 is provided on the opposite side of rotor 41 within the body section 14. The annular recess 78 is connected by means of a plurality of drilled passages 9t and 91 extending axially between the pressure chamber and the Referring now to the FIGS. 2 and 3, there is illustrated a partially sectional view of the rotor, vanes, and associated fluid inlet and fluid outlet working chambers. In order to insure that a proper seal is maintained at the transition zones B and C between the inlet port 28 and the outlet port 74 and between the inlet port 30 and the outlet port 72 as the vanes traverse respectively from the inlet to the output ports in a clockwise direction as is viewed in FIG. 2, there is provided around the outer periphery of the rotor a plurality of drilled bores or slots 82, each of which is located between adjacent vanes and loosely fitted within each of the slots 82 there is provided a pin 84 which extends the width of rotor 41.

As is illustrated in FIG. 3, a portion of the bores 82 4 open to the outer periphery of the rotor at 83-. The pin 84 annular recess '78 and are illustrated in FIG. 1. and the bore 82 are sized in such a manner that the pin 84 will abut the cam track while traversing the transition zones C to B, but does not engage both lips of the opening 83, thus, pressure fluid will be communicated through the opening 83 from the inter-vane space associated with each pin to the under pin portion of bore 82 forcing the pin into a fluid sealing relation with the cam track.

As is further illustrated in FIG. 3, the radial movement of the pin during operation is restricted by the configuration of the machined containment slot lips at 83 such that the pin, whose cross section is greater than that of the lips, will contact the cam surface only during that portion of the revolution of the rotor in which the pins are traversing the transition zones extending from B to C.

This contact of the pin 8% with the cam track before contact with the lip 83 is due to the small clearance between the rotor outer periphery and the cam track during the transition zone extending from B to C.

As can be clearly seen in FIG. 3, the pressure will act on one side of the pin 84 as it passes through the transition portion extending from B to C and is simultaneously forced into contact with both the cam track and a portion of the pin containment slot. Clearance between the pin 84 and the lip 83 insures pressure beneath the pin. Thus, as the rotor rotates through a cycle the device, the sealing pin 84 will prevent fluid communication between the inlet and outlet ports as the same crosses over the transition portion extending from B to C, whereas, the same sealing pins 'ill have no efiect on the pumps performance through the remainder of the cyclical operation. This latter operation is due to the lips 83 which limit the radially outwardly movement of the pins so as to prevent pin-cam track contact during the remainder of the cycle.

Referring now to the FIGS. 4 and 5, there is shown another embodiment of the present invention. With the exception or" some additional elements, the components illustrated in FIGS. 4 and 5 are respectively identical to the elements illustrated in FIGS. 2 and 3, and therefore, are identified by the same numerals.

Referring now to the figures, a pair of arcuate recesses 92 and 9 are formed on pressure plate 38 within the true are portion extending from B to C and are connected to the high pressure chamber by means of drill passageways 96 and 98, respectively. There is also provided across the true are portions B through C within the body member 1 3, a pair of arcuate shaped ports, not shown, which are opposite the recesses 92 and 94 for the purpose of balancing the pressures acting across rotor 41. The recesses 92 and 94 are provided for supplying high pressure fluid to the pin slots 82 which, in turn, act on the pins 84 to force the same into engagement with the cam track during the transition of the vanes through the transition portions extending from B to C, and thus to prevent leakage between the same in the same manner as described above in the description of the operation of the device illustrated in FIGS. 1 and 2.

Referring now to FIG. 6, there is shown another embodiment of the present invention in which the pressure fluid in the inter-vane spaces associated with each pin is transmitted to the inner surface of pin '84 within the pin slot 82 by means of a plurality of passageways 100 extending from the outer periphery of the rotor to the pin slot 82. The passageways 100 transmit the cyclically changing'pressure which is exerted on the outer edges of the pins as they traverse from the inlet zone to the outlet zone via the transition portions extending from B to C. Their effect on the pins and the performance of the pump is the same as the embodiment described hereinbefore in the description of the operation of the device illustrated in FiuS. 1 and 2, but are provided to insure a proper fluid connection between the inter-vane spaces and the bore 82,.

It can thus be seen that the pins 84 located between the vanes to provide a secondary means for sealing the inlet and outlet zones during the transition of the vanes between the same has provided a means for increasing the annular distance between the vanes required without sacrificing porting size.

It can also be seen that the reduction in the number of vanes required for both pumps and motors will result in a stronger rotor segment which will contribute to the attainment of higher operational levels; all of which can be accomplished without increasing either the cost or the overall dimensions of devices presently in production.

It can also be seen that the sealing means permits the inlet and discharge ports to be extended further into the ramp, thus allowing more. time not only for acceleration of the vanes, but an increase in the time for filling and discharging the intervane space, with the resultant effect that erosion and noise is greatly reduced.

While the form of embodiment of the invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within thescope of the claims which follow.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. A fluid pressure energy translating device including a plurality of low and high pressure passages some of which are inlet passages and the others outlet passages; a cam track having a plurality of inlet pressure and outlet pressure ramps respectively associated with said plurality of inlet and outlet passages; a rotor rotatably mounted within said cam track having a plurality of slots formed therein; a plurality of pumping elements mounted within said slots, one end of each element being adapted to abut the track and the inter-element spaces bet-ween the outer periphery of said rotor and said cam track undergoing alternate phases of expansion and contraction as the pumping elements traverse the cam track ramps during a cycle of the device; a plurality of transition portions on said cam track connecting said ramps to each other, some of said transition portions being within close proximity to said rotor outer periphery; means forming a sealing element carried by said rotor between each of said pumping elements, said sealing elements being movable outwardly from said rotor outer periphery into a fluid sealing relation with said cam track transition portions which are within a close proximity to said rotor outer periphery in response to the inter-element pressure acting thereon; and means for restricting the outwardly movement of said sealing elements to a predetermined amount, whereby said sealing means prevents direct fluid communication between said inlet and outlet pressure ramps across said cam track transition portions which are within a close proximity to said rotor outer periphery.

2. A fluid pressure energy translating device as described in claim 1 wherein said pumping elements are a plurality of vanes slidably mounted within each of said rotor slots.

3. A fluid pressure energy translating device as described in claim .1 wherein the outwardly movement of said sealing elements is limited by an abutment with said cam track while traversing. said transition portions which are within close proximity to the rotor outer periphery whereas said restricting means limits the outwardly movement of said sealing elements during the remainder of the cycle of the device.

4. A fluid pressure energy translating device as described in claim 1 wherein each of said sealing elements is movably mounted within a plurality of second slots formed within said rotor between each of said pumping elements and the outwardly movement of said sealing elements is limited by the abutment with said cam track while traversing said transition portions which are within a close proximity to said rotor outer periphery, whereas, said restricting means limits the outwardly movement of said sealing elements during the remainder of the cycle of the device.

5. A fluid pressure energy translating device of the type described in claim 4 wherein said sealing means being a pin of a generally circular cross section disposed within each of said second slots, said second slots being of a generally circular cross section and extending across the width of said rotor outer periphery, the inner portion of said second slots being of a greater cross section than said pin, while that portion of said second slot opening to the outer periphery of said rotor is of a cross section which is less than that of said pin so as to limit the outwardly movement of said pin.

6. A fluid pressure energy translating device as described in claim 5 wherein said pumping elements are vanes, each of which is slidably mounted within said firstmentioned slots.

7. A fluid pressure energy translating device as described in claim 4 including passage means extending from the outer periphery of said rotor to the second slot for communicating the cyclically changing inter-vane pressure associated with the pin disposed in said slot in timed relationship with the expansion and contraction phases of the inter-vane space associated with said pin.

8. A fluid pressure energy translating device as described in claim 4 including means connecting the high pressure operating passage to each of said slots for the purpose of forcing said pin disposed in each of said slots outwardly into abutment with the said transition portions which are within a close proximity to said rotor outer periphery as the same traverses said transition portions.

9. A fluid pressure energy translating device as described in claim 31 wherein each of said sealing elements is mova'bly mounted Within a plurality of second slots formed within said rotor between each of said pumping elements.

10. A fluid pressure energy translating device as described in claim 9 wherein said restricting means is formed within said second slot.

11. A fluid pressure energy translating device as described in claim 9 wherein the outwardly movement of said sealing elements is limited by the abutment with said cam track while traversing said transition portions which are within a close proximity to said rotor outer periphery Whereas said restricting means limits the outwardly movement of said sealing elements during the remainder of the cycle of the device.

12. A fluid pressure translating device as described in claim 11 wherein said sealing means being a pin of a generally circular cross section disposed within each of said second slots, said second slots being of a generally circular cross section and extending across the width of said rotor outer periphery, the inner portion of said sec ond slots being of a greater cross section than said pin, while that portion of said second slot opening to the outer periphery of said rotor is of a cross section which is less than that of said pin so as to limit the outwardly move ment of said pin.

13. A fluid pressure energy translating device as described in claim 12 wherein said pumping elements are vanes, each of which is slidably mounted within said first-mentioned slots.

14. A fluid pressure energy translating device as described in claim 9 including passage means for connecting the cyclically changing inter-element pressure to the inner ends of said sliding elements within each of said second slots in timed relationship with the expansion and contraction phases of the inter element spaces associated with each of said second slots.

15. A fluid pressure energy translating device as described in claim 9 including means connecting said high pressure operating passage to each of said second slots beneath said associated sealing elements to force the same outwardly as said sealing elements traverse said one transition portion which are within a close proximity to said rotor periphery.

16. A fluid pressure energy translating device as de scribed in claim 11 including passage means extending from the outer periphery of said rotor to each of said second slots for communicating the cyclically changing inter-vane pressure associated with the pin disposed in each of said slots in timed relationship with the expansion and contraction phases of the inter-vane spaces associated with said pin.

17. A fluid pressure energy translating device as described in claim 11 including means connecting the high pressure operating passages to each of said slots for the purpose of forcing said pin disposed in each of said slots outwardly into abutment with the said transition portions which are within a close proximity to said rotor outer periphery as said second slots traverse the same.

18. As a new article of manufacture for use within a cam track of a fluid energy translating device comprising:

a rotor having a plurality of substantially radial slots extending from the periphery of the rotor;

a pumping element slidably mounted within each of said slots the outer end of which is adapted to engage said cam track;

said rotor having a plurality of bores of a substantially circular cross section extending through its width, a portion of each of said bores opening into the outer periphery of said rotor, said bores each being located between each of said pumping elements; and,

a plurality of sealing elements disposed within each of said rotor bores and being adapted for radially outwardly movement in response to fluid pressure acting thereon, each sealing element being a pin of substantially circular cross section, each said bore having a cross section which is greater than said pin, while each of said pins has a cross section greater than said bore openings.

19. An article of manufacture as described in claim -18 wherein said pumping elements are a plurality of vanes slidably mounted with said rotor slots.

20. An article of manufacture as described in claim 19 including a passage-way connecting each of said bores to the outer periphery of said rotor within the intervane space associated with each bore.

2 1. In a rotary vane fluid energy translating device comprising a rotor having a plurality of radially sliding vanes, the outer ends of which engage a vane track having two diametrically opposed inlet ramps and two diametrically opposed outlet ramps; said vane track having a minor transition zone between one terminus of each outlet and inlet ramp and having a major transition zone between the other terminus of each inlet and outlet rarnp, the spacing between the outer periphery of the rotor and the vane track being less at said minor transition zones than at said major transition zones; that improvement comprising:

a plurality of sealing elements, one between each pair of vanes including means for urging said sealing elements toward said vane track;

and means for limiting the movement of said sealing elements a predetermined amount wherein said sealing elements engage said vane track only while crossing the minor transition zones of the vane track and are disengaged from said track while crossing the major transition zones and the inlet and outlet ramps.

22. A fluid pressure energy translating device, as described in claim 21, wherein said sealing elements comprise pins shiftable within bores opening to the periphery of said rotor.

23. A fluid pressure energy translating device, as described in claim 22, 'Wherein lips formed at the open end of each bore comprise the sealing elements movement limiting means.

References Cited UNITED STATES PATENTS 331,939 12/1885 Blair 103136(A)UX 855,590 6/1907 Ripberger 103l36 2,725,013 11/1955 Vlachos 103136(A)UX 3,016,019 l/1962 Rineer 103l36(A)UX 3,306,228 2/1967 Drutchas 103-136X 3,469,500 9/1969 Lutz et a1. 103-136X C. J. HUSAR, Primary Examiner U.S. Cl. X.R. 418143, 225 

